BA 134 then BA 746 at Heathrow
Mumbai → London → Geneva
Timetable, London time
12:35BA 134 from Mumbai at the gate
10:30BA 746 to Geneva leaves the gate
21 h 55 apart on the timetable, overnight
BA 746 leaves 21 h 55 after BA 134 arrives on the timetable: more than half a day, so not a connection we count.